DE1098119B - Device for welding metallic plates to large metallic bodies by means of a current surge - Google Patents

Description

Device for welding metallic plates to metallic ones Large body by means of a current surge The invention relates to a device for welding from platelets to large bodies, in particular from feather tips to spring bodies, by means of Current surge in which both workpieces are held in brackets so that they can move against one another are, using mechanical energy stored by the release of electrical switches that take effect suddenly.

When welding metal plates or tips, see below only called platelets, on nibs it is common to use a nib blank to be arranged in a storage or to be held in a clamp and the plate to be arranged in a holder that is mounted vertically below the spring blank and to bring the plate into contact with the spring or vice versa, whereupon a welding circuit, which is fed from a direct current source and in which includes the pen clip and the wafer holder, closed the temperature increase occurring at the point of contact causing the melting the nib point and the flowing apart of the metal of the same over the Causes platelets. The welding current is then switched off, and with that As a result of the cooling of the metal, the plate is attached to the nib blank welded on. Then the pen is withdrawn to its original position, the fully welded spring is taken out of the clamp and replaced with a new one Reed tube replaced; a new plate is automatically fed into the container and repeats the sequence of operations described above.

To monitor the time during which the welding current flows through Various methods have been used in the past. So can he Welding circuit z. B. contain a pair of cooperating contacts, which means a rotating control cam can be opened and closed, the rotating control cams by a suitable motor with constant speed is driven. In another arrangement, the welding circuit is controlled in such a way that that he of the movement of the plate in the spring body when connecting the Metal is dependent on the same, so that it is automatically switched off when a predetermined corresponding movement of the same has taken place; are here electrical switches have also been used, which are saved by releasing mechanical energy suddenly become effective.

With spring tip welding using a welding device with a capacitor surge discharge works, it is already known to use weight-operated switches for on and off Switch off the capacitor charging current to use.

Upon investigation of this problem, it has been found that it is necessary to the temperature in the welding zone and the total amount of heat applied to it to be controlled very precisely in order to achieve that a successful welding of a number metallic platelets on a number of metallic base bodies, e.g. B. on feather tips, in continuous operation it is achieved in such a way that all welds are equally healthy and similar or matching external appearance and metallurgical properties exhibit.

Accordingly, the aim of the invention is to provide a device for welding to create metallic platelets on metallic base body, which is easy and is efficient and which is precisely reproducible from weld to weld Results made possible by the fact that the duration of the welding current through the welding zone can be determined and controlled with extreme accuracy.

The invention consists in the fact that the welding current is and is switched off by a pendulum time switch whose pendulum is in front or is automatically held in working position after completion of each work sequence and which has an adjustable cam device which is actuated by means of the pendulum at whose movement is actuated from the working position and the movable contact the switching mechanism closes and opens.

The plate holder is expedient at one end of a horizontal one Arm attached that swivels in a horizontal plane and at an angle along it two circular arcs of the same or different radius length adjustable is stored, the centers of the arcs in spaced apart There are pivot points which are offset from one another by 90 ° in the plane.

A preferred embodiment is characterized by one of a motor-driven shaft with a control cam for moving the chip holder away from the holder for the base body, a control cam for the platelet feed to the wafer holder and another control cam, which controls the supply of hydrogen to the platelet holder controls and the pendulum releasable in the loaded position holds, wherein the first-mentioned control cam carries a projection with the Pendulum engages and brings this into the loaded position.

The adjustable cam device expediently includes a pair Control cam with complementary control surfaces that are relative to each other are rotatable and lockable to each other in any desired angular position and one of which is firmly connected to the control camshaft, to which the Pendulum is attached.

In the following an embodiment of the invention is applied with reference to the welding of metallic platelets on nib blanks described on the drawing.

Fig. 1 shows the front view of a pen welding machine according to the invention; Figure 2 is a perspective view of the machine from the rear and with the housing removed; 3 shows a perspective view of the spring tip clamping device; Figure 4 is a top plan view of the main drive shaft and associated parts including the pendulum timing device; FIG. 5 is a detailed view of the welding contacts and the control cams, which get their drive; Figure 6 shows a top plan view of the die holder mounting and adjustment facilities, and Figure 7 shows a wiring diagram for the circuit.

According to FIGS. 1 and 2, the machine has a frame 1 with a Base plate 2 and a vertical front wall 3. On the base plate and the wall are the different parts of the machine assembled, usually in one housing are included, which is not shown in the drawing.

On the outside of the wall 3 is a clamping device 4 for springs mounted, and below this device 4 is a vertically displaceable holder 5 arranged for platelets, which will be described in more detail later with reference to FIG. 6 The type to be described is mounted so that it is exactly below the tip of the pen can be set up, which is held by the spring clip 4.

The spring clamping device 4 and the holder 5 for the platelets are Components of a direct current welding circuit 6 (see Fig. 7), which is powered by a 12 V accumulator 7 (Fig.7) is supplied with energy and an adjustable resistor 8 and includes a pair of cooperating contacts 9 and 10 operated by a shuttle timer can be periodically opened and closed, generally denoted by the reference symbol 11 is provided. After a plate has been brought up through the plate holder 5 and this has been brought into contact with the spring clamping device 4 is, in a manner described below, the welding current flows when closing the circuit 6 by closing the contacts 9 and 10.

The resistor 8, by means of which the amplitude of the current surge is determined is advantageous in the form of a resistance switch box in screw plug design variable in steps of 1/2 Siemens from 0 to 80 Siemens. If wanted, This box can contain an induction coil to control the degree of increase in the welding current to monitor.

On the base plate 2 is a bearing block 12, to which the front and the rear uprights 13 and 14, between which the shaft 15 is mounted which carries a pulley 16 by means of which the shaft 15 is driven by an electric motor 17 is driven via a chain 18. For controlling the engine is. on the Wall 3 a main control switch 17 a is provided.

The motor 17 has a band brake device 17 b, the band 17 c of which is normally held in a free or relieved position against the action of a spring 17 d by means of a solenoid 17 e which is connected to the band brake 17 c by an arm 17 f. The solenoid 17e is connected to the circuit of the motor 17, so that when said circuit is closed, the solenoid 17e is energized, so that the spring 17d counteracts and disables the brake; however, if the circuit of the motor is interrupted, the solenoid 17e drops out, and the brake 17c is activated by the spring 17d.

A control cam 19 is mounted on the shaft 15 (Figs. 2 and 4), with which a roller 20 cooperates on one end of a rod or a piston 21 is attached, which is in a storage funnel 22 for platelets can slide. The rod 21 is connected to the control cam 19 by means of a spring 23 kept engaged and intermittently operated by said control cam 19 set, whereby each plate from the supply funnel 22 over the chute 22a falls into the aforementioned wafer holder 5. The design and the method of operation of the funnel 22 are not such as to require further explanation, and accordingly it is also not shown or described in detail herein.

The shaft 15 also carries a control cam 24, which for Operation of the valve control mechanism to control the supply of hydrogen serves during the welding process to the plate holder 5, of which only one Part 25 is shown in FIG. The control cam 24 is on one side with a provided axial curve 26, which serves to hold the holding device 27 against the To hold the effect of the spring 27 a in such a position that the pendulum is in the high position remains, as shown in Figure 4.

Another control cam 28 is mounted at the front end of the shaft 15, which acts via a roller 29 on one end of the arm 30, the other End carries a downwardly directed bolt 31 which is operative with the holder 5 for the Plate is connected and serves to act of the control cam 28 to move the holder 5, against the action of a Spring away from spring clip 4.

Further ahead of said control cam 28, between it and the front wall 3 of the frame 1, there is a standing bearing block 32, in which a shaft 33 is rotatably mounted, the axis of which is parallel to the shaft 15, however is offset sideways from it. On the shaft 33 is the pendulum timer 11 with a pair of relatively adjustable control cams 34 and 35 and one Pendulum 36 mounted.

The construction and the mode of operation of the device 11 are described in more detail below. At this point it suffices to note that the pendulum 36 is normally held by the holding device 27 in the raised position shown in bold lines in FIGS. 2 and 4 and, during operation, swings into the horizontal position shown in broken lines in FIG which it is held by a locking device 37 under spring pressure. The pendulum 36 is returned to its starting position by a part 38 which projects laterally from the control cam 28 and which engages with a lateral projection 39 of the pendulum 36 when the control cam 28 rotates.

An off switch is located on the stand 14 in the vicinity of the control cam 19 40 attached, which is in the circuit of the motor 17. The switch 40 has one Arm 41, which in the rest position by the against the rear side of the control cam 19 directional pressure of a spring is held in such a position that he holds switch 40 in the closed position so that the motor and solenoid circuits are closed when the main switch 17u is closed.

The control cam 19 carries a protruding one on the mentioned side surface Part 42 which engages with the end of the arm 41 when the control cam 19 is rotated occurs and this moves backwards, so that the switch 40 and thus the circuits of the motor 17 and the solenoid 17e are opened.

In this way, the spring 17d is released and the band 17c of the braking device 17b, whereby the motor 17 and the shaft 15 come to a standstill come while the arm 41 is still engaged with the protruding part 42.

So that the motor 17, if necessary, put back into operation can be and at the same time the brake not shown in the drawing is released, is to temporarily short-circuit the switch 40 and thus close the circuits of the motor 17 and the solenoid 17e a push button switch 42a (Fig.1) intended.

The construction of the clamping device 4, the support and adjustment devices for the wafer holder 5 and the pendulum timer 11 are now described in detail.

As can be seen from Fig. 3, the spring clamping device 4 has two cooperating parts, namely the stationary part 43, which is attached to the front wall 3, and a movable part 44. The stationary part 43 contains a block 45 on a base plate 46 is mounted in such a way that it protrudes laterally over the front wall 3 of the machine, and which has two tongues 47 in the front, which are displaceable and lockable and are arranged at an obtuse angle to one another in the plane of said front of the block 45. The opposing, adjacent ends of the tongues are beveled in the shape of a V to accommodate the spring tip blank. At right angles to the aforementioned tongues 47 and projecting backwards beyond the block 45 at the same angle to the vertical as the tongues 47 have, a further tongue 48 extends from the V-shaped part, which in the block 45 by means of the opposite Clamping pieces 49, which are fixed to the block 45 by screws 50, is clamped. The tongues 47 can be locked in any setting to one another by means of the clamping screws 51, whereby the distance by which a spring tip blank protrudes over the V-shaped part which is formed by the ends of said tongues 47 is adjusted relative to the chip holder 5 as desired can be.

On the base plate 46, an arm 53 is articulated at 52, which the movable Contains part 44 of the clamping device. This arm 53 carries in a slot 54, the cut into the arm is a tongue 55 which is angled to the perpendicular Level of the arm is and has a beveled inner end 55 a, which is extends into said vertical plane and with the beveled in the same way End of the fixed tongue 48 can cooperate to form a nib tip blank to clamp between them when said arm 53 is in abutment in the closed position is swung with the stationary block 45. The arm 53 is closed Position held by means of a toggle lever 56.

Part 57 provides a micrometer gauge for adjusting the upward movement of the plate holder 5, which this may perform when the metal of the spring blank melted during the welding process, this movement of the holder 5 is controlled by a protruding part 5 a, which is located on the holder 5 and strikes against the micrometer gauge 57.

As shown in FIGS. 4 and 5, the control cam 35 is fixedly mounted on the shaft 33 which carries the pendulum 36, and can accordingly rotate together with it. The adjacent control cam 34 can rotate freely on the shaft 33 and can be fixed in any desired angular position relative to the control cam 35 by means of the clamping screw 58. The control cam 34 is formed with sections of radii of different sizes, namely with a section 34a with a larger radius and a section 34b with a smaller radius. In accordance therewith, the control cam 35 is designed with a section with a larger radius 35 a and a section with a smaller radius 35 b corresponding to the section 34 b. By rotating the control cam 34 relative to the control cam 35, the two control cams can be adjusted so that they form a control surface in which the effective length of the surface with the smaller radius can be changed.

A stationary bracket 59 is arranged on the bearing block 22 and carries the stationary contact 9 at its free end. A spring 60 is also attached to the bracket 32, to which an arm 61 is connected, at the end of which a roller 62 is mounted, which is held in engagement with the control cams 34 and 35 by the spring 60. Separated from the roller 62 and also carried by the arm 61 , the contact 10 is attached, which cooperates with the fixed contact 9 mentioned above.

As shown in the drawing, the spring 60 is loaded in order to keep the contacts 9 and 10 separated from each other when the roller 62 runs over the control cam parts with the outer or larger radius 34 a and 35 a. However, when the roller 62 runs over the inner or the part with the smaller radius of both control cams 34b and 35b, the contacts 9 and 10 are brought together under the action of the spring 60 in order to close the welding circuit.

According to FIG. 3, the container or holder 5 has a component 5 b with a conical recess for holding the tips and receiving a spring which is brought in from the spring clamping device 4, which has been described above. This component 5 b is surrounded by a cylindrical sheath 5 c.

As can be seen from FIGS. 2 and 6, the holder 5 is supported by a carrier 65 worn, the construction and assembly of which is described below and the is pressed upwards by the spring 66 (FIG. 2) in the rest state.

In order to be able to align the holder 5 exactly below a spring tip that is clamped in the spring clamp 4, the profile support 65 is designed as a right-angled triangular component, the two acute-angled corners of which are supported by joints 67 and 68, which are at the opposite ends of an adjustable , rotatable bearing rail 69 are attached, which extends along the hypotenuse of the triangular support 65 and parallel to it. The bearing rail 69 is slidably mounted on a horizontal table 70 , which is built into the frame 1 of the machine, where it can be adjusted by means of the adjusting screws 71 and 72 which are fastened to said table 70 and by means of which said bearing rail 69 can be adjusted, is held.

The plate holder 5 is at the right-angled corner 65 a of the triangular Carrier 65 mounted.

In this arrangement, by actuating the adjusting screw 71, the bearing rail 69 is rotated together with the carrier 65 and, in this way, the chip holder 5 is pivoted on an arc of a circle 73. In the same way, by actuating the adjusting screw 72, the carrier 65 is rotated and the plate holder is pivoted on a circular arc 74. The plate holder 5 is accordingly adjustable via two axes that are essentially perpendicular to one another and in this way can be aligned exactly below a spring tip in the tip clamp 4.

To carry out a welding process, the mechanisms described above work together in the following way: It should be assumed that the work sequence of a weld has been completed and that the parts are ready for carrying out a further welding process, that is, the plate holder 5 is in the lower position as a result of the Activity of the control cam 28, the pendulum 36 of the pendulum time switch device 11 is in its high position after it - the drive motor 17 at the end of the previous welding process is swiveled counterclockwise over the vertical upwards and at an angle of about 30 ° to the vertical has been brought into rest position, in which it is temporarily held by the action of the detachable projection 39 on the holding device 27, while the contacts 9 and 10 in the welding circuit 6 are kept separate because the roller 62 on the movable contact arm 10 during this rotary movement the tax Cams 34 and 35 of the pendulum device 11 has remained in contact with the outer or larger radius parts of the control cams 34 and 35 and the contact arm 61 has consequently been held in its original position in which the contacts 9 and 10 are separated.

At the same time, the arm 41 is still open with the protruding part 42 the control cam 19 engaged so that the motor and solenoid circuits are opened and the brake is applied. At this point there is also no feather tip in the tip clamping device 4, but there is a plate in the container or holder 5. In Fig. 2, the parts are in the position described above with respect to one another shown.

To perform another welding operation, the tip clamp is used 4 initially opened in that the toggle lever 56 is released and that the arm 53 pivots into the position shown in FIG. The operator then puts a nib blank in its place between the tongues 47, and in such a way that it protrudes slightly from underneath and is held there while the Arm 53 is pivoted into the closed position, whereby the spring blank in its Position clamped and locked by means of the toggle lever 56.

The operator then actuates the pushbutton switch 42a, by means of which the switch 40 is short-circuited and the circuits of the motor 17 and the solenoid 17e are closed. In this way, the brake 17b is released and the shaft 15 starts rotating. The push-button switch 42a is depressed until the arm 41 has left the protruding part 42, and is then released, since the current through the switch 40 is now closed.

The following operations then run: First, through Rotation of the control cam 28 of the holder 5 is released, whereupon he acts his spring 66 moves upwards until the plate which is already in it, comes into contact with the protruding end of the spring blank.

At this point the welding circuit 6 is open except for those that are still open Contacts 9 and 10 closed. The parts are now ready for execution prepared for welding.

Upon further rotation of the shaft 15, the surface 26 of the control cam 24 can then retract the holding device 27 under the action of the spring 27a. The pendulum 36 released in this way swings downward as a result of gravity and assumes a horizontal position, which is shown in dotted lines in FIG. 4 and in which it is temporarily held by the locking device 37 which is under spring pressure. This angular movement of the pendulum 36 causes further rotation of the control cams 34 and 35, which are coupled to the same, so that the roller 62 runs on the inner or the parts with the smaller radius 34 b and 35 b of the control cam surface and the contact arm 61 allowed to move under the action of its spring 60 and to close the switches 9 and 10, which remain closed until the roller 62 runs again on the outer control cam surface 34 ca and 35 a during the swing of the pendulum 36 in the horizontal position.

When contacts 9 and 10 close, a current flows from it Accumulator 7 by the Welding circuit 6 (Fig. 7) in which a spring blank 76 and a plate 77 are included in the holder 5, with the result that the increase in temperature due to the resistance at the point of contact the metal of the spring blank 76 between the spring blank 76 and the plate 77 melts and spreads over the plate 77. The holder 5 rises now as a result of the action of its spring 66 further upwards against the body of the spring blank 76, until it is through the protruding part 5 a, which is located on the holder 5, comes into contact with the previously set micrometer screw gauge 57 and to Hold is forced. During this process, the control coke 24 has the valve control mechanism 25 set in motion so that hydrogen can flow into the container 5 with the plate can.

When the roller 62 runs up again on the outer control cam surfaces 34a and 35a, the contacts 9 and 10 are again separated from one another, and the welding circuit will be interrupted. Since only a small part of the pen 76 over the spring clip 4 protrudes, the developed heat spreads rapidly, the metal of the pen 76, which surrounds the plate 77, cools down very quickly as soon as the welding circuit is activated is switched off, and the plate 77 is welded to the pen 76.

The length of time during which the sweat flows through the predetermined length of the inner and smaller surfaces of the control cams 34 b and 35b determined, depending on the requirements by rotating the control cam 34 and 35 are adjusted against each other as described above. In practice it can this time can vary from about 0.005 to 0.20 seconds, and it is advantageous when it approaches the lower time limit as closely as possible.

The 12 V accumulator from which the welding current is drawn is advantageously uninterrupted by a known type of supercharger (not shown), which is capable of a constant electromotive force of 13.5 V ± 2d / o. The current surge flowing through the welding zone can be regulated by the operator from 30 to 1000 amps as required.

When the shaft 15 continues to rotate, it is actuated by the drive motor 17 the control cam 28, the arm 30 and the support pin 31, whereby the now empty holder 5 against the pressure of the spring 66 is guided downward out of the welding zone to its initial rest position.

Then the rod or the piston 21 is actuated by the control cam 19 moved in the hopper 22, thereby removing a single wafer from the one therein stored stack slides through the chute 22 a into the holder 5. to At the same time, the control cam 28 has rotated so far that the projection 38 with the lateral projection 39 on the horizontally lying pendulum 36 in engagement occurs. With further rotation of the control cam 28, the pendulum 36 is up over the vertical pivoted out into a position in which the projection 39 with the holding device 27 comes into engagement, which in the meantime by the Movement of the control cam surface 26 of the control cam 24 into its projecting working position has been brought.

The parts have now returned to their initial positions, and the arm 41 of the switch 40 runs over the 1st orspring 42 on the control cam 19, opening the switch 40 and making the brake 40a effective, so the motor 17 and the shaft 15 to bring to a standstill. The welded pen is now removed from the spring clip 4, a new spring blank is inserted into it in the manner previously described, and after restarting the motor 17 by pressing the pushbutton switch 42a, the above sequence of operations is repeated.

While in the above a particular application of the invention on the basis of a Example has been described, it is understood that within the scope of the invention Changes can be made to it. For example, the feed needs one new plate to the container or holder and the return of the pendulum timer not to be carried out in the superscript at the end of a welding process, but these operations can, if desired, at the beginning of the sequence of the operations take place.

Claims (4)

PATENT CLAIMS: 1. Device for welding platelets to large bodies, in particular spring tips to spring bodies, by means of a current surge, in which both workpieces are held in brackets so that they can be moved against each other, using electrical switches that suddenly become effective due to the release of stored mechanical energy, characterized that the welding current is switched on and off once by a pendulum time switch device (11), the pendulum (36) is automatically held in the working position before or after completion of each work sequence and which has an adjustable control cam device (34, 35), which by means of of the pendulum (36) is actuated when it moves out of the working position and closes and opens the movable contact (9) of the switching mechanism. 2. Apparatus according to claim 1, characterized in that the plate holder (5) is attached to one end of a horizontal arm (65) which is in a horizontal Pivotable plane and at an angle along two arcs (73, 74) of matching or adjustable in different radius lengths, the center points of the circular arcs lie in pivot points (67, 68) that are at a distance from one another, which are offset from one another by 90 ° in the plane. 3. Device according to claim 1 or 2, characterized by a shaft driven by a motor (17) a control cam (28) for moving the wafer holder (5) from the holder for the base body, a control cam (19) for the platelet feed to the platelet holder and a further control cam (24), which the supply of hydrogen to the The plate holder controls and the pendulum (36) can be released in the loaded position holds, wherein the first-mentioned control cam (28) carries a projection (38) which comes into engagement with the pendulum and brings it into the loaded position. 4. Apparatus according to claim 3, characterized in that the adjustable control cam means includes a pair of control cams (34, 35) with complementary control surfaces (34a, 35a) which are rotatable relative to one another and can be locked in any desired angular position to one another and of which one (34) is firmly connected to the control camshaft (33) to which the pendulum (36) is also attached. Considered publications: German Patent Specifications No. 1007 899, 1 012 711, 951328; Swiss Patent No. 195 356; U.S. Patent Nos. 2,005,752, 2,226,322, 2,688,065, 2167 925, 2,129,845, 2,024,597.